Your question:
My baby is six months old and she's started making kind of a wheezing noise when she breathes in. It sounds like she can't catch her breath. Could this be a sign of asthma?

The expert answers: Babies at six months are full of curiosity and just starting to learn how to communicate verbally. They quickly learn what gets the attention of the people around them. If your baby makes these sounds only occasionally and then smiles at you when you look at her, she's playing a game called "Look at me!" and has found a way to be sure that she gets your attention quickly. This making of a sound to start a social interaction is the very beginnings of communication and later language.

However, if these sounds occur while she is sleeping, or otherwise occupied or if she seems to be having trouble catching her breath, then you should definitely contact your pediatrician so s/he can listen to your baby to see if there are any breathing problems.